What is the stab trim range?

What is the stab trim range?

• A. -13 to +2
• B. +2 to -13
• C. 0 to +2
• D. -2 to +13

Answer: (A)

Stabilizer trim range shows how far the horizontal stabilizer can move to set the aircraft’s pitch, and it’s measured in degrees of stabilizer deflection. For the CRJ-550, the limits are -13 to +2 degrees, where negative means nose-down trim and positive means nose-up trim. This asymmetric range is design-driven: you can move the nose down quite a bit to counter tendencies that push the nose up, but only a small amount of nose-up trim is allowed to keep handling safe and to preserve elevator authority. So the published limits are -13 to +2 degrees. Other choices either flip the direction, omit part of the range, or extend beyond what the aircraft permits, which is why they don’t match the real specification.

Stabilizer trim range shows how far the horizontal stabilizer can move to set the aircraft’s pitch, and it’s measured in degrees of stabilizer deflection. For the CRJ-550, the limits are -13 to +2 degrees, where negative means nose-down trim and positive means nose-up trim. This asymmetric range is design-driven: you can move the nose down quite a bit to counter tendencies that push the nose up, but only a small amount of nose-up trim is allowed to keep handling safe and to preserve elevator authority. So the published limits are -13 to +2 degrees. Other choices either flip the direction, omit part of the range, or extend beyond what the aircraft permits, which is why they don’t match the real specification.